Hi got the same kernel as you I found out about my previously error and wrote wrong bus id and now I got the same error as you but I don't have VGA_SWITCHEROO built in

Well removing VGA_SWITCHEROO didn't have any impact (this would have been too easy).
Nevertheless from what I read I would advise removing it when using proprietary drivers.

Well I wonder if the following has anything to do with my problem and maybe yours my dear fellow dcd94.
from end of dmesg

Code:

[ 10.479141] vgaarb: this pci device is not a vga device
[ 10.792870] vgaarb: this pci device is not a vga device
[ 82.715413] vgaarb: this pci device is not a vga device
[ 82.767100] vgaarb: this pci device is not a vga device

NVIDIA appear has 3D controller and not something like VGA compatible controller:
?
I read something about a patch for vgaarb to allow it to recognize 3D controller. I don't know if this has been implemented in kernel.

I don't know if this is a good lead or not.

Maybe dcd94 if you can post the result of lspci | grep 'VGA\|NVIDIA' , check if your demsg got something like " vgaarb: this pci device is not a vga device".
Also
If someone with a NVIDIA card showing up as 3D controller in lspci result got it working using proprietary optimus config from NVIDIA I appreciate if you can do a quick post to let me know that this is not an issue.

If someone with a NVIDIA card showing up as 3D controller in lspci result got it working using proprietary optimus config from NVIDIA I appreciate if you can do a quick post to let me know that this is not an issue.

But I run into exactly same issue as you did, xorg is seagfoulting in the very same moment, my Xorg.0.log is looking almost the same as yours one.
Also on amd64 arch. If anyone know how to deal with this please let me know._________________Dell XPS Gentoo 3.12.2 GCC 4.8.2 KDE 4.11

well I am not sure what could be the cause.
I don't think the 3D controller in showing in lspci has anything to do with that.

andrzejk you have a different nvidia card(GeForce GT 540M vsGT 620M ) than me and a different intel VGA contoller (second generation vs 3 generation).
but we both have the same X segfault
We should have something in common that make X segfault but what?

I think this should have to do with a config option somewhere (kernel?)or a wrong set-up from our part.

grep VGA /usr/src/linux/.config
CONFIG_VGA_ARB=y
CONFIG_VGA_ARB_MAX_GPUS=6
# CONFIG_VGA_SWITCHEROO is not set
# CONFIG_VGASTATE is not set
# CONFIG_FB_SVGALIB is not set
# CONFIG_FB_VGA16 is not set
CONFIG_VGA_CONSOLE=y
CONFIG_VGACON_SOFT_SCROLLBACK=y
CONFIG_VGACON_SOFT_SCROLLBACK_SIZE=128
# CONFIG_LOGO_LINUX_VGA16 is not set
# CONFIG_USB_SISUSBVGA is not set

with Frambuffer(not using UVESA)?

Code:

CONFIG_FB=y
# CONFIG_FB_DDC is not set
CONFIG_FB_BOOT_VESA_SUPPORT=y
CONFIG_FB_CFB_FILLRECT=y
CONFIG_FB_CFB_COPYAREA=y
CONFIG_FB_CFB_IMAGEBLIT=y
# CONFIG_FB_CFB_REV_PIXELS_IN_BYTE is not set
# CONFIG_FB_SYS_FILLRECT is not set
# CONFIG_FB_SYS_COPYAREA is not set
# CONFIG_FB_SYS_IMAGEBLIT is not set
# CONFIG_FB_FOREIGN_ENDIAN is not set
# CONFIG_FB_SYS_FOPS is not set
# CONFIG_FB_WMT_GE_ROPS is not set
# CONFIG_FB_SVGALIB is not set
# CONFIG_FB_MACMODES is not set
# CONFIG_FB_BACKLIGHT is not set
CONFIG_FB_MODE_HELPERS=y
CONFIG_FB_TILEBLITTING=y
# CONFIG_FB_VGA16 is not set
# CONFIG_FB_UVESA is not set
CONFIG_FB_VESA=y
CONFIG_FB_EFI=y

Also, I can't enable external display. The following worked flawlessly with Intel, but doesn't work now:

Code:

xrandr --output VGA-0 --right-of LVDS-0 --mode 1360x768

TwinView is greyed in nvidia-settings (which attempts to generate a weird pre-optimus aged xorg.conf for static setups), so I have no options to connect the display, and I *suspect* that it still would require to restart X server to change display config with NVIDIA graphics -- so bad for the laptop mode._________________Commit code back to ALSA, save your latency and CPU: rm /usr/bin/pulseaudio;touch /usr/bin/pulseaudio;chattr +i /usr/bin/pulseaudio

Section "Screen"
Identifier "nvidia"
Device "nvidia"
# Uncomment this line if your computer has no display devices connected to
# the NVIDIA GPU. Leave it commented if you have display devices
# connected to the NVIDIA GPU that you would like to use.
#Option "UseDisplayDevice" "none"
EndSection

If someone with a NVIDIA card showing up as 3D controller in lspci result got it working using proprietary optimus config from NVIDIA I appreciate if you can do a quick post to let me know that this is not an issue.